A chrome plating replacement film that can be used in an extrusion method, a vacuum-pressure molding method, a mold integrated injection molding method and the like is needed in order to omit harmful chrome plating processing. Furthermore, if the chrome plating replacement film can be used in the extrusion of an automobile belt line molding, a part can be made lighter through a reduction in an amount of stainless steel used, and a problem with metal/resin mixed waste will also not occur. A paint replacement film is effective in improving a work environment because there are no Volatile Organic Compounds (VOC) or any spray mist.
Polyolefin is light, inexpensive, and harmless, and thus most promising as a resin for automobile parts. However, polyolefin-based resins, particularly polypropylene-based resins, are difficult to apply to paint, metal, film and the like, and are referred to as hardly adhesive materials.
The vacuum-pressure molding method and the mold integrated injection molding method are becoming more commonly used as application methods for a decorative film or sheet thereof. Use of these molding methods is required in order to completely cover a deeply-drawn three-dimensional object as this type of three-dimensional object cannot be covered with a decorative film or sheet by conventional manual labor.
Patent Publication No. 3851523B describes a “metallic luster sheet for three-dimensional molding having a transparent thermoplastic resin film, a metal layer, an adhesive layer, and a thermoplastic resin film in that order, wherein the transparent thermoplastic resin film is configured of a polyester-based polymer compound having a cyclohexane ring and a benzene ring in a main chain, or a polyester-based polymer compound having and a naphthalene ring and a benzene ring in a main chain.”
Japanese Unexamined Patent Application Publication No. 2006-341388A describes a method that is “A molding method for a thermoforming laminated sheet that molds a thermoforming laminated sheet having 1) a thermoplastic resin film layer, 2) a decorative layer having a metal vapor deposition layer or a highly bright ink layer with metallic luster containing thin metal strips and binding resin, and 3) a supporting substrate resin layer at a molding temperature of (T1−20°) C. to (T2+35°) C. Here, T1 is either a softening temperature of the thermoplastic resin film layer or a softening temperature of the supporting substrate resin layer, whichever is higher, and T2 is either the softening temperature of the thermoplastic resin film layer or the softening temperature of the supporting substrate resin layer, whichever is lower.”